NASA sure does know how to drag out the kooks. NASA's innovative new project for studying the Moon's chemistry and attempting to detect water involves effectively slamming a projectile into the Moon's surface and analyzing the resulting ejecta. The Register reports on the crazies who are concerned about the US government's latest 'bombing campaign':
He wasn't alone, either, with various observers backing the surrealists' possible belief that NASA might inadvertently cause major havoc with their crater strike. This might seem to be impossible given the bigness of the Moon, the smallness of the LCROSS, and the laws of physics - but there were those who disagreed. Commentard Greenstar perhaps summed up this point of view best:
Think of the planets in terms of forming a sentence. The Earth is a noun. The moon is a verb. Its very existance creates action in the tides, the weather, and possibly human mood. It's perfection of rotation sets into play all the components that make it possible for life here to exist and yet no life exists there. How is that possible? Wouldn't it seem logical for the earth to have a reciprocal effect on the moon - but it doesn't. The laws of symbiosis don't apply. If the moon is nothing more than a big rock then it can be cleaved like a big rock. Laws of mass and density don't apply nor do they offer us protection from the idiots at NASA who have never watched a diamond cutter. They are big boys with BIG toys and brains the size of a TRex AND are running the risk of making us all extinct.
In the meantime. The reality-based community can follow the LCROSS project at NASA's LCROSS website
Showing posts with label technology. Show all posts
Showing posts with label technology. Show all posts
Dr. Gans
Carl Gans, a giant in the field of comparative and functional morphology, has died at 86.
Dr. Gans has left a profound and lasting impact on vertebrate anatomy and evolution. His work with Glenn Northcutt laid foundations for modern ideas on the role of neural crest in the evolution of the vertebrate head. He was the editor of the 23-volume Biology of the Reptilia, a remarkable source of ideas and data on reptile biology and evolution.
Obituaries: NY Times; CNAH
Tip to Palaeoblog
MacBook Pro
This was a frustrating and disappointing part of my day:
After lunch, I opened my year-old MacBook Pro from its slumber to find a nice set of off-center racing stripes down my screen. Turns out, they go away if I jostle the monitor panel a bit, but that's not going to cut it. The vertical lines will reappear and continue to remind me of the cheap and overrated engineering.
I'm very disappointed by this. My options right now are either to pay to get it fixed or pay to get a new computer. I can't stand the thought of going back to Windows, really. However, the thought of giving Apple another cent of my money is really putting me off. This one forum thread alone can regale you with 12 pages of anecdotes about this same problem with MacBook Pros. Even while under warranty, some folks have gone through three or more new computers—or so the stories say.
UPDATE: Apple has kindly offered to cover the costs of the repair. It's still rather disappointing though.
After lunch, I opened my year-old MacBook Pro from its slumber to find a nice set of off-center racing stripes down my screen. Turns out, they go away if I jostle the monitor panel a bit, but that's not going to cut it. The vertical lines will reappear and continue to remind me of the cheap and overrated engineering.
I'm very disappointed by this. My options right now are either to pay to get it fixed or pay to get a new computer. I can't stand the thought of going back to Windows, really. However, the thought of giving Apple another cent of my money is really putting me off. This one forum thread alone can regale you with 12 pages of anecdotes about this same problem with MacBook Pros. Even while under warranty, some folks have gone through three or more new computers—or so the stories say.
UPDATE: Apple has kindly offered to cover the costs of the repair. It's still rather disappointing though.
Maybe some redemption can be found in parody.
This review, and all seven subsequent parts made my day.
Some graphic images
There's been a report of a snake with a legs and toes in the media recently. The blogosphere has some interesting comments on it, too. Most notably, there is skepticism. Take a look at our snake in question here:
In a comment on Pharyngula, Jerry Coyne notes:
Some graphic images below the fold illustrate why this is not unreasonable speculation.
Snakes sometimes consider their prey choices poorly. Here's a snake with legs and two tails:
(Hat tip to Febble)
Oops! I sort of skipped the first comment at Pharyngula. This commenter noted first that it was probably something the snake ate. Moreover, they note a fact I forgot to mention in my haste: the limb is quite far from where we'd expect the hindlimb to be, if one were to show up. It would be much closer to the tail, not at mid-length of the body. It should be at approximately the same level as the cloaca. There's the unlikely case that it's an atavistic forelimb however, which would raise the issue of where a snake's neck begins or ends.
In a comment on Pharyngula, Jerry Coyne notes:
I suspect that this snake ingested a lizard, and that the lizard's limb simply burst through the side of the snake. I may be wrong, and I hope so, because this is great evidence for evolution.
Some graphic images below the fold illustrate why this is not unreasonable speculation.
Snakes sometimes consider their prey choices poorly. Here's a snake with legs and two tails:
(Hat tip to Febble)
Oops! I sort of skipped the first comment at Pharyngula. This commenter noted first that it was probably something the snake ate. Moreover, they note a fact I forgot to mention in my haste: the limb is quite far from where we'd expect the hindlimb to be, if one were to show up. It would be much closer to the tail, not at mid-length of the body. It should be at approximately the same level as the cloaca. There's the unlikely case that it's an atavistic forelimb however, which would raise the issue of where a snake's neck begins or ends.
Taphonomy is the branch of research
There are good papers, great papers, and those clever little papers that make you say "I wish I'd thought of that!". Before I get to that, a little preamble:
Taphonomy is the branch of research that is interested in describing what happens to an organism between dying and ending up as a fossil (or even why it won't end up as a fossil). A lot can happen to an organism in that period of time, as the earth is a dynamic spheroid. The older a fossil, the more possible disturbances it can experience. Taphonomy can tell us a lot about the environment an organism was deposited in and it can provide important controls on the inferences we make about the environment we think a fossil organism once lived in. But taphonomy is also an important consideration in considering what an organism is. That is, the 'life' of a fossil after death, might have a profound impact on how we place that fossil in the tree of life.
Enter the experiments of Rob Sansom and colleague's experiments on lamprey larvae and the title organism of this blog, reported in this week's issue of Nature. Sansom et al. wanted to examine what happens to 'primitive' vertebrates that lack hard, mineralized tissues, the type of tissues that normally fossilize. I say "normally", because there are some 'abnormal' cases in which soft-bodied creatures with no bones, teeth, or hard cuticles actually form as fossils. Some such fossils have played an important role in understanding the timing and early origin of vertebrate animals.
For instance, this species known as Yunnanozoon (Chen et al. 1999) from the Cambrian of China. It represents one of the earliest known vertebrates or vertebrate-like forms.
Yunnanozoon is remarkably well preserved, but other Cambrian chordates can be even more incomplete. The problem with such fossils is that they're difficult to interpret because they're squished, and they're made of soft parts. We have no idea how much they might have decayed, apart from the fact that they seem to be an exception to the rule that soft parts don't fossilize. This usually implies some sort of exceptional conditions favouring preservation, but doesn't necessarily rule out decay or other types of disruption.
Sansom et al. let larval lamprey and lancelets rot in buckets of sea water and recorded the progress of the decay over the period of several months.
The impressive and startling results of watching fish decay are below the fold:
As the animals rotted away, Sansom et al. recorded details of their anatomy. Not just general features, but the types of characters that would be used to score an organism for a phylogenetic analysis. These include classically important features, like the gill filaments, cartilages of the gill arches, the type of heart, the shape of the body muscles, the dorsal rod known as a notochord, and so on. These are characters that have normally played a significant role in establishing the relationships of vertebrates and their nearest non-vertebrate relatives, such as the lancelet.
What this figure shows is the length of time each character survived as the animal rotted. What's striking is that the characters that lasted longer all tend to be characters that we consider phylogenetically more primitive. Characters such as a notochord and segmented axial musculature are all considered to be primitive features shared by the last common ancestor of lancelets and lamprey. On the other hand, features such as eyes, or a chambered heart are more derived features found in modern vertebrates.
This figure shows nicely how the decay features plot out in phylogenetic history. If you go back to figure above, there is a graph showing the relationship between phylogenetic rank and decay stage.
What we see is that the level of decay would lead one to think that the taxon was signicantly more distantly related to the vertebrates, much like the early chordates we find in the Cambrian.
Not only do these results provide a caution against how we interpret soft-bodied Cambrian chordates, but it illustrates a framework for studying the phylogenetic effects of decay. As decay is studied across a wider phylogenetic scope, the more we can determine about the generality of these types of patterns. That will have a profound effect on how we study and interpret the exceptional cases of soft-tissue preservation in fossils.
Chen, Y.-J., Huang, D.-Y., and Li, C.-W. 1999. An early Cambrian craniate-like chordate. Nature 402:518-522 link
Sansom, R.S., Gabbott, S.E., and Purnell. M.A.2010. Non-random decay of chordate characters causes bias in fossil interpretation. Nature 463:797-800 link
Briggs, D.E.G. 2010. Palaeontology: Decay distorts ancestry. Nature 463:741-743 link
Taphonomy is the branch of research that is interested in describing what happens to an organism between dying and ending up as a fossil (or even why it won't end up as a fossil). A lot can happen to an organism in that period of time, as the earth is a dynamic spheroid. The older a fossil, the more possible disturbances it can experience. Taphonomy can tell us a lot about the environment an organism was deposited in and it can provide important controls on the inferences we make about the environment we think a fossil organism once lived in. But taphonomy is also an important consideration in considering what an organism is. That is, the 'life' of a fossil after death, might have a profound impact on how we place that fossil in the tree of life.
Enter the experiments of Rob Sansom and colleague's experiments on lamprey larvae and the title organism of this blog, reported in this week's issue of Nature. Sansom et al. wanted to examine what happens to 'primitive' vertebrates that lack hard, mineralized tissues, the type of tissues that normally fossilize. I say "normally", because there are some 'abnormal' cases in which soft-bodied creatures with no bones, teeth, or hard cuticles actually form as fossils. Some such fossils have played an important role in understanding the timing and early origin of vertebrate animals.
For instance, this species known as Yunnanozoon (Chen et al. 1999) from the Cambrian of China. It represents one of the earliest known vertebrates or vertebrate-like forms.
Yunnanozoon is remarkably well preserved, but other Cambrian chordates can be even more incomplete. The problem with such fossils is that they're difficult to interpret because they're squished, and they're made of soft parts. We have no idea how much they might have decayed, apart from the fact that they seem to be an exception to the rule that soft parts don't fossilize. This usually implies some sort of exceptional conditions favouring preservation, but doesn't necessarily rule out decay or other types of disruption.
Sansom et al. let larval lamprey and lancelets rot in buckets of sea water and recorded the progress of the decay over the period of several months.
The impressive and startling results of watching fish decay are below the fold:
As the animals rotted away, Sansom et al. recorded details of their anatomy. Not just general features, but the types of characters that would be used to score an organism for a phylogenetic analysis. These include classically important features, like the gill filaments, cartilages of the gill arches, the type of heart, the shape of the body muscles, the dorsal rod known as a notochord, and so on. These are characters that have normally played a significant role in establishing the relationships of vertebrates and their nearest non-vertebrate relatives, such as the lancelet.
What this figure shows is the length of time each character survived as the animal rotted. What's striking is that the characters that lasted longer all tend to be characters that we consider phylogenetically more primitive. Characters such as a notochord and segmented axial musculature are all considered to be primitive features shared by the last common ancestor of lancelets and lamprey. On the other hand, features such as eyes, or a chambered heart are more derived features found in modern vertebrates.
This figure shows nicely how the decay features plot out in phylogenetic history. If you go back to figure above, there is a graph showing the relationship between phylogenetic rank and decay stage.
What we see is that the level of decay would lead one to think that the taxon was signicantly more distantly related to the vertebrates, much like the early chordates we find in the Cambrian.
Not only do these results provide a caution against how we interpret soft-bodied Cambrian chordates, but it illustrates a framework for studying the phylogenetic effects of decay. As decay is studied across a wider phylogenetic scope, the more we can determine about the generality of these types of patterns. That will have a profound effect on how we study and interpret the exceptional cases of soft-tissue preservation in fossils.
Chen, Y.-J., Huang, D.-Y., and Li, C.-W. 1999. An early Cambrian craniate-like chordate. Nature 402:518-522 link
Sansom, R.S., Gabbott, S.E., and Purnell. M.A.2010. Non-random decay of chordate characters causes bias in fossil interpretation. Nature 463:797-800 link
Briggs, D.E.G. 2010. Palaeontology: Decay distorts ancestry. Nature 463:741-743 link
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